Piston ring



NOV. 10, 1931. c NORTON 1,831,574

PISTON RING Filed May 26, 1930 T 1 El i 6. NORTON amnion abtowwq Patented Nov. 10, 1931 UNITED STATES ERNEST c. NORTON, F llIIOLINE, ILLINOIS PISTON RING Application filed May 26, 1930. SerialNo 455,527.

The present inventionpertains to two-piece piston rings and to the means for causing the same to exert substantially equal pressure upon the cylinder walls throughout practically the entire extentof the outer surface of the ring. It is well-known that the one-piece ring is so cut that it exerts considerable pressure outwardly against the cylinder wall but it is not so well known that the wear resulting from this outward pressure reduces the thickness of the two ends of the ring. It is also still less well-known that as the ring expands to contact with the wall of the cylinder, the part of the ring opposite the two ends moves inwardly toward the center of the ring so that the ring at this point does not fit closely against the cylinder wall. However, this fact has been proven beyond any question of doubt and it is there fore one of the objects of this invention to so construct a ring that the pressure of the outer surface of the ring against the cylinder wall will be substantially equal at all points. It is also a well known fact that the plural piece ring used in combination with the corrugated spring which is placed between the ring and the bottom of the groove in the piston causes an undue amount of wear on the cylinder walls, thus necessitating reboring of same more often than should be necessary. It is therefore an object of this invention to provide a ring which will not exert undue pressure upon the cylinder wall and will therefore not cause undue wear thereof.

Another object of the present invention is to provide a ring which will be an improvement over that disclosed in my prior Patent No. 1,607,77 9, November 23, 1926. My invention further resides in the combination, construction and arrangement of parts illustrated in the accompanying drawings and, while I have shown therein what is now considered the preferred embodiment of this invention, I desire the same to be understood as illustrati e only and not to be interpreted in a limiting sense.

In the drawings annexed hereto and forming'a part hereof, Fig. 1 is a section through a piston ring, the same being shown as being surrounded by a wall representative of a cylinder wall, though the same is not intended toac'curately represent the same. Fig. 2shows an expanded View of the piston ring and the spring which causes separation of the ring parts.

Reference will now be made in greater de- 7 tail to the annexed drawings wherein the piston ring parts are designated by the numeral 1 and the spring by which these are forced into contact with the cylinder wall by the numeral 2. This spring is roughly elliptical in form with the two ends spacedapart somewhat. The sections of the ring and their ends are cut away in part so as to provide overlapping ends as is customary.- The in ner faces of the ring sections are grooved as indicated at 3 for the reception and retention of the spring 2. This spring is cut of just such a length that, when inserted between the two ring sections and theseare fully pressed together, the two ends of the spring will just PA N omen about meet at the point 4;. When the ring is inserted in the groove of the piston and then placed in the cylinder, there will be a little expansion of the ring beyond the surface of the piston and this will cause slight separation of the ring sections as indicated at 5. It will also cause a slight separation of the ends of the spring as indicated at 4. These separations are somewhat exaggerated in order to indicate clearly that the separation takes place.

By a careful examination of Fig. 1 it will be seen that the parts (Sand 7 of the spring2 are in intimate contact withthe inner surface of the ring sections 1 but that the intermediate parts in the vicinity of the gaps 5 are out of contact therewith. These latter portions have a tendency to press against the bottom of the piston ring groove in the Wall of the piston and therefore to cause radial pressure against the piston ring sections wherever the spring is in contact with the rm I i, has been found by extensive tests that there is no appreciable difference in the wear on the ring sections. when they are pressed 7 outwardly by an elliptical shaped spring such as shown in Fig. 2, while the same can not be said of other types of construction. It

will be seen by examination of Fig. 1 that the ring tends to expand so as to contact at all points with the wall of the cylinder as represented by the part marked 8 in Fig. 1.

Having now described my invention, I claim:

1. An internally grooved two-piece ring in combination with a generally elliptical spring, the major diameter of the spring extending transverse to the diameter of the ring connecting two ends of a single section.

2. A piston ring and means for holding same in contact with the interior wall of a cylinder, said ring comprising a pair of ring sections grooved on their inner faces and adapted to receive in the grooves an actuating spring, and a ring of spring material substantially circular in cross section, discontinuous at one point, and of a generally oval shape, one end of the oval including the ends of the spring member, said spring memher being adapted to have its ends in contact with the bottoms of the grooves in the ring sections and being adapted to be compressed into substantially a circle when the ring sections are applied to the spring and compressed until their ends contact.

3. A two-piece piston ring and means for maintaining same in contact with the internal wall of a cylinder comprising an oval shaped spring, the ends of whose major diameter press against substantially the midpoint in the length of the ring sections when 1n use.

In Witness whereof, I hereunto subscribe my name to this specification.

ERNEST C. NORTON. 

